Moreno-Maroto, Alonso-Azcárate, J. J.MMartínez-García, Romero, M. C.López-Delgado, Cotes-Palomino, T A.2024-02-072024-02-072022-10-29Moreno-Maroto, J.M.; Alonso-Azcárate, J.; Martínez-García, C.; Romero, M.; López-Delgado, A.; Cotes-Palomino, T. Zeolitization of Diatomite Residues by a Simple Method. Appl. Sci. 2022, 12, 10977. https://doi.org/10.3390/app1221109772076-3417https://doi.org/10.3390/app122110977https://hdl.handle.net/10953/2196Abstract The possibility of transforming a diatomite-rich waste from the brewing industry into synthetic zeolites has been investigated. After precalcination at 550 °C to eliminate the retained organic matter, the clean diatomite (Dt; with a Si/Al molar ratio of 17.4), was hydrothermally treated for 24 h with continuous stirring in a 3M NaOH solution at 80 °C. The results of mineralogical characterization by X-ray diffraction with Rietveld refinement have shown a crystallization of 55% of zeolite P, which was neoformed from the amorphous phase, opal-CT and quartz of the starting sample. The spectra obtained by Fourier Transform Infrared Spectrometry have corroborated such zeolitization. N2 adsorption–desorption isotherms have shown that the zeolitized material (Dt-Z) is mesoporous, with almost 60% more specific surface area than Dt (62.6 m2/g vs. 39.4 m2/g), greater microporosity and 40% smaller average pore size than Dt (71 Å vs. 118 Å). This study is a first approximation to know the potential of diatomite wastes as zeolite precursors, for which additional research including an aluminum source will be required.engCC0 1.0 Universalhttp://creativecommons.org/publicdomain/zero/1.0/diatomitewaste valorizationhydrothermal synthesisNaOHinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccess